Network interface sharing methods and apparatuses that support kernel mode data traffic and user mode data traffic

ABSTRACT

Methods and apparatuses are provided that allow kernel mode data traffic and user mode data traffic to share a common network communication port. One apparatus includes user mode logic, kernel mode logic, and kernel mode to user mode interface logic. The interface logic is configured to receive data packets and selectively distribute the data packet to either the user mode or kernel mode logic. The interface logic includes “virtual” bridge logic and “virtual” miniport logic. The bridge logic determines if a received data packet is a user mode or kernel mode data packet. If it is a kernel mode data packet, then the bridge logic provides the data packet to the kernel mode logic. If it is a user mode data packet, then the bridge logic stores the data packet in memory for subsequent use by the user mode logic. The bridge logic also receives outgoing kernel mode data packets from the kernel mode logic and provides them to a network communication port, and retrieves outgoing user mode data packets from memory and provides them to the same network communication port. The miniport logic provides an interface between the memory accessed by the bridge logic and user mode logic. The miniport logic accepts outgoing user mode data packets and stores them in the memory for subsequent access by the bridge logic, and retrieves incoming user mode data packets stored in memory by the bridge logic.

RELATED APPLICATIONS

This application claims priority under 35 U.S.C. §120 as a continuationof U.S. patent application Ser. No. 10/021,592, filed Oct. 30, 2001 nowU.S. Pat No. 7,007,157, and titled “Network Interface Sharing Methodsand Apparatuses that Support Kernel Mode Data Traffic and User Mode DataTraffic”, the entire disclosure of which is hereby incorporated byreference in its entirety.

TECHNICAL FIELD

The present invention relates generally to data communications, and moreparticularly to improved methods and apparatuses that can be implementedin various communicating devices to support the transmission andreception of both kernel mode data and application level (user mode)data via a shared network interface.

BACKGROUND

A data communication environment typically includes at least two devicesthat are operatively coupled together through at least one networkconnection. By way of example, a device may include a computer and/orcommunicating device, and the network may include a packet switchednetwork or the like. The device would usually include a processor thatis configured to run programs (logic) including, for example, anoperating system and one or more applications, etc. The processor may beconsidered to be running in either a kernel mode or a user mode,depending on the program(s) actively running at a given moment.

One common form of kernel mode logic is a debugging program thatprovides a tool for understanding how the processor and programmed logicare functioning. Such debugging often occurs during the manufacture ofthe device and/or programming of the device. To better understand howthe device is performing, there may be a need to monitor the operationof the device at various times during which it is running in user mode.For example, it may be beneficial to periodically monitor variousparameters associated with the device as it is communicates or attemptsto communicate with another process or device.

In certain instances, this and other similar types of debugging mayrequire the communication of both user mode data packets and kernel modedata packets. For devices configured with at least two physical networkcommunication ports, this does not present a problem since one port canbe configured to support the user mode related communications andanother port can be configured to support the kernel mode relatedcommunications. However, there are some devices that are configured withonly one physical network communication port. For example, certain WorldWide Web accessing devices or appliances are configured with a singleEthernet (IEEE 802.3) or like communication port in order to reducecosts, size and/or complexity.

Typically, if a manufacture of such a device wanted to conduct debuggingor other like testing, then a conventional serial or parallel datacommunication interface would be added/used. This may increase the cost,size and/or complexity of some devices. Such serial or parallelcommunication ports tend to be significantly slower than a networkcommunication port, which may hamper the testing process. Moreover, thedevice may not be able to be tested in this manner once the end user hasinstalled it, because the network communication port will likely be theonly operative communication port. If testing is allowed, then thenormal use of the device may be interrupted while the testing isconducted.

Consequently, there is a need for methods and apparatuses that allowkernel mode data traffic, such as, for example, debugging data packets,and user mode data traffic to share a common network communication port.

SUMMARY

Methods and apparatuses are provided that allow kernel mode data trafficand user mode data traffic to share a common network communication port.

In accordance with certain implementations of the present invention, forexample, the above stated needs and others are met by an apparatushaving user mode logic, kernel mode logic, and kernel mode to user modeinterface logic. The interface logic is configured to receive datapackets and selectively distribute the data packet to either the usermode logic or the kernel mode logic, as so determined. In certainimplementations, the interface logic includes bridge logic and miniportlogic.

In one example, the bridge logic is configured to determine if areceived data packet is a user mode data packet or a kernel mode datapacket. If the received data packet is a kernel mode data packet, thenthe bridge logic provides the data packet to the kernel mode logic. Ifthe received data packet is a user mode data packet, then the bridgelogic stores the data packet in memory for subsequent retrieval/use bythe user mode logic. The bridge logic is further configured to receiveoutgoing kernel mode data packets from the kernel mode logic and toprovide the outgoing data packets to a network communication port. Thebridge logic is also configured to retrieve outgoing user mode datapackets from the memory and to provide these outgoing data packets tothe same network communication port.

In this example, the miniport logic is configured to provide aninterface between the memory accessed by the bridge logic and user modelogic. Thus, for example, the miniport logic accepts outgoing user modedata packets and stores them in the memory for subsequent access by thebridge logic, which typically would run in kernel mode. The miniportlogic also accesses or otherwise retrieves incoming user mode datapackets from the memory after they have been stored there by the bridgelogic, and provides these data packets to the user mode logic. Here, theuser mode logic would typically run in user mode.

With this exemplary apparatus, both user mode and kernel mode datapackets can be sent/received through one communication port. In certainimplementations, the communication port may include a network, such as,for example, a TCP/IP network, perhaps including the Internet.Consequently, given such an apparatus and by selectively switchingbetween kernel and user modes, kernel mode logic such as, e.g.,debugging logic, may be run on a networked device while the device isalso allowed to run user mode logic that also requires a networkcommunication capability. Given such an apparatus, debugging operationscan be conducted without significantly interrupting or otherwiseinterfering with the operation of the device being debugged.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete understanding of the various methods and apparatuses ofthe present invention may be had by reference to the following detaileddescription when taken in conjunction with the accompanying drawingswherein:

FIG. 1 is a block diagram that depicts an exemplary environment whereintwo or more devices are arranged to communicate through at least onenetwork connection, in accordance with certain implementations of thepresent invention.

FIG. 2 is a block diagram that depicts a general architecture forcertain exemplary types of communicating/computing devices.

FIG. 3 is a block diagram that depicts an arrangement for sharing acommon communication port to send/receive user mode data and kernel modedata, in accordance with certain exemplary implementations of thepresent invention.

FIG. 4 is a flow diagram that depicts a shared communication port datapacket transmission process, in accordance with certain exemplaryimplementations of the present invention.

FIG. 5 is a flow diagram that depicts a shared communication port datapacket reception process, in accordance with certain exemplaryimplementations of the present invention.

DETAILED DESCRIPTION

Turning to the drawings, wherein like reference numerals refer to likeelements, the invention is illustrated as being implemented in asuitable computing environment. Although not required, the inventionwill be described in the general context of computer-executableinstructions, such as program modules, being executed by a computer orlike device. Generally, program modules include routines, programs,objects, components, data structures, etc. that perform particular tasksor implement particular abstract data types. Those skilled in the artwill recognize that the logical functions described herein are suitablefor implementation in hardware, firmware and/or software, depending uponthe targeted device.

FIG. 1 is a block diagram depicting an exemplary data communicationenvironment 100 having at least two devices that are operatively coupledtogether through at least one network. Here, for example, device A 102is connected to device B 104 through network 106.

Devices A 102 and B 104 are representative of any device that is capableof sending and/or receiving data via network 106. Thus, by way ofexample, device A 102 may include a personal computer (PC), a networkappliance, a personal digital assistant (PDA), a web companion, a mobiletelephone, and/or other like devices. In certain exemplaryimplementations, device A 102 includes an embedded network communicationcapability that allows device A 102 to send/receive transmission controlprotocol/Internet protocol (TCP/IP) data packets. In this example,device B 104 may take the form of a remote server or like device that isconfigured to exchange data over network 106 with device A 102.

In certain implementations device B 104 is specifically configured tosupport debugging processes associated with the operation of device A102. Such debugging processes would typically require a debuggingprocess operating within device A 102 to receive commands/data from, andprovide resulting data to, a corresponding debug controlling processoperating within device B 104. One example of this type of a debuggingoperation is that which is conducted by the original equipmentmanufacturer (OEM) of device A 102. Here, for example, network 106 mayinclude a local area network (LAN) that allows the OEM to debug (e.g.,monitor, test, modify, etc.) the operation of device A 102 using deviceB 104.

As mentioned above in the Background section, to reducecosts/size/complexity, certain devices are manufactured with one networkcommunication port, such as, for example, an IEEE 802.3 (i.e., Ethernet)port. To debug such a device it may be necessary tocapture/monitor/measure various parameters within the operating system(OS) kernel while the device is supporting application levelcommunications via the network communication port. Unfortunately, sincethe application level communications require the use of the only networkcommunication port, the debugging commands/data to/from the OS kernelcannot be transmitted through the network communication port. Hence,OEMs of conventional devices have tended therefore to add or otherwiseutilize a typically slower serial or parallel data communicationinput/output (I/O) port to provide a path for the debuggingcommands/data between the device being debugged and asupporting/controlling device.

For simplicity, the term “data” as used herein is intended to includeany type of data, including command or control data, communication data,raw data, processed data, etc. In certain exemplary implementations thedata is provided in the form of one or more data packets. Here, the datapackets can be defined as being either kernel mode generated datapackets or application level (user mode) generated data packets, basedon the generating process or processes and/or intended recipientprocess/processes.

In accordance with certain aspects of the present invention, methods andapparatuses are provided which allow user mode data and kernel mode datato be transmitted/received through a single, shared or commoncommunication port. Thus, for example, in the exemplary OEM debuggingoperation described above the kernel mode debugging data can betransmitted/received through the same network communication port beingused to transmit/receive user mode data. As such, the communicationbandwidth supporting the debugging operation will usually be higher thanthat associated with a serial or parallel port. Also, in certainimplementations device A 102, for example, can be configured without anadditional serial or parallel port.

Attention is now drawn to the block diagram depicted in FIG. 2. FIG. 2illustrates an example of a conventional computing environment 120, ofwhich all or part may be implemented within either device A 102 anddevice B 104 to support the various methods and apparatuses describedherein.

Exemplary computing environment 120 is only one example of a suitablecomputing environment and is not intended to suggest any limitation asto the scope of use or functionality of the improved methods andarrangements described herein. Neither should computing environment 120be interpreted as having any dependency or requirement relating to anyone or combination of components illustrated in computing environment120.

The improved methods and apparatuses herein are operational withnumerous other general purpose or special purpose computing systemenvironments or configurations. Examples of well known computingsystems, environments, and/or configurations that may be suitableinclude, but are not limited to, personal computers, server computers,thin clients, thick clients, hand-held or laptop devices, multiprocessorsystems, microprocessor-based systems, set top boxes, programmableconsumer electronics, network PCs, minicomputers, mainframe computers,distributed computing environments that include any of the above systemsor devices, and the like.

As shown in FIG. 2, computing environment 120 includes a general-purposecomputing device in the form of a computer 130. The components ofcomputer 130 may include one or more processors or processing units 132,a system memory 134, and a bus 136 that couples various systemcomponents including system memory 134 to processor 132.

Bus 136 represents one or more of any of several types of busstructures, including a memory bus or memory controller, a peripheralbus, an accelerated graphics port, and a processor or local bus usingany of a variety of bus architectures. By way of example, and notlimitation, such architectures include Industry Standard Architecture(ISA) bus, Micro Channel Architecture (MCA) bus, Enhanced ISA (EISA)bus, Video Electronics Standards Association (VESA) local bus, andPeripheral Component Interconnects (PCI) bus also known as Mezzaninebus.

Computer 130 typically includes a variety of computer readable media.Such media may be any available media that is accessible by computer130, and it includes both volatile and non-volatile media, removable andnon-removable media.

In FIG. 2, system memory 134 includes computer readable media in theform of volatile memory, such as random access memory (RAM) 140, and/ornon-volatile memory, such as read only memory (ROM) 138. A basicinput/output system (BIOS) 142, containing the basic routines that helpto transfer information between elements within computer 130, such asduring start-up, is stored in ROM 138. RAM 140 typically contains dataand/or program modules that are immediately accessible to and/orpresently being operated on by processor 132.

Computer 130 may further include other removable/non-removable,volatile/non-volatile computer storage media. For example, FIG. 2illustrates a hard disk drive 144 for reading from and writing to anon-removable, non-volatile magnetic media (not shown and typicallycalled a “hard drive”), a magnetic disk drive 146 for reading from andwriting to a removable, non-volatile magnetic disk 148 (e.g., a “floppydisk”), and an optical disk drive 150 for reading from or writing to aremovable, non-volatile optical disk 152 such as a CD-ROM, CD-R, CD-RW,DVD-ROM, DVD-RAM or other optical media. Hard disk drive 144, magneticdisk drive 146 and optical disk drive 150 are each connected to bus 136by one or more interfaces 154.

The drives and associated computer-readable media provide nonvolatilestorage of computer readable instructions, data structures, programmodules, and other data for computer 130. Although the exemplaryenvironment described herein employs a hard disk, a removable magneticdisk 148 and a removable optical disk 152, it should be appreciated bythose skilled in the art that other types of computer readable mediawhich can store data that is accessible by a computer, such as magneticcassettes, flash memory cards, digital video disks, random accessmemories (RAMs), read only memories (ROM), and the like, may also beused in the exemplary operating environment.

A number of program modules may be stored on the hard disk, magneticdisk 148, optical disk 152, ROM 138, or RAM 140, including, e.g., anoperating system 158, one or more application programs 160, otherprogram modules 162, and program data 164.

The improved methods and arrangements described herein may beimplemented within operating system 158, one or more applicationprograms 160, other program modules 162, and/or program data 164.

A user may provide commands and information into computer 130 throughinput devices such as keyboard 166 and pointing device 168 (such as a“mouse”). Other input devices (not shown) may include a microphone,joystick, game pad, satellite dish, serial port, scanner, camera, etc.These and other input devices are connected to the processing unit 132through a user input interface 170 that is coupled to bus 136, but maybe connected by other interface and bus structures, such as a parallelport, game port, or a universal serial bus (USB).

A monitor 172 or other type of display device is also connected to bus136 via an interface, such as a video adapter 174. In addition tomonitor 172, personal computers typically include other peripheraloutput devices (not shown), such as speakers and printers, which may beconnected through output peripheral interface 175.

Computer 130 may operate in a networked environment using logicalconnections to one or more remote computers, such as a remote computer182. Remote computer 182 may include many or all of the elements andfeatures described herein relative to computer 130.

Logical connections shown in FIG. 2 are a local area network (LAN) 177and a general wide area network (WAN) 179. Such networking environmentsare commonplace in offices, enterprise-wide computer networks,intranets, and the Internet.

When used in a LAN networking environment, computer 130 is connected toLAN 177 via network interface or adapter 186. When used in a WANnetworking environment, the computer typically includes a modem 178 orother means for establishing communications over WAN 179. Modem 178,which may be internal or external, may be connected to system bus 136via the user input interface 170 or other appropriate mechanism.

Depicted in FIG. 2, is a specific implementation of a WAN via theInternet. Here, computer 130 employs modem 178 to establishcommunications with at least one remote computer 182 via the Internet180.

In a networked environment, program modules depicted relative tocomputer 130, or portions thereof, may be stored in a remote memorystorage device. Thus, e.g., as depicted in FIG. 2, remote applicationprograms 189 may reside on a memory device of remote computer 182. Itwill be appreciated that the network connections shown and described areexemplary and other means of establishing a communications link betweenthe devices may be used.

With the various components and functions described above in mind,attention is drawn to the block diagram of an apparatus 200 in FIG. 3,which depicts certain components and functions that may be operativelyconfigured within device A 102 (FIG. 1), in accordance with certainexemplary implementations of the present invention. While this exampleis directed towards a TCP/IP network, those skilled in the art willrecognize that the methods and/or apparatuses taught herein areapplicable/adaptable to other data communication protocols/schemes.

As shown, a communication port 202 is configured to send and receivedata packets, such as, user mode data packets U1 214 and U2 218, andkernel mode data packet K1 216. A kernel mode process referred to hereinas “virtual” bridge logic 204 is operatively configured to provide orotherwise identify outgoing data packets (either user or kernel mode) tocommunication port 202 and receive or otherwise identify incoming datapackets (again, either user or kernel mode) from communication port 202.Bridge logic 204 is configured to provide a multiplexing-like,port-sharing capability that allows user mode data packets to besent/received through communication port 202 along with kernel mode datapackets. Here, bridge logic 204 operates in kernel mode.

To accomplish this port-sharing task, bridge logic 204 is operativelycoupled to a kernel mode debugging process 206, for example. Kernel modedebugging process 206, in this exemplary arrangement, is configured tosupport debugging operations associated with OS kernel 158. Bridge logic204 is configured to receive data packets from communication port 202and determine if the received data packets are either user mode orkernel mode data packets. If the received data packet is determined tobe a kernel mode data packet, for example, associated with kernel modedebugging process 206, then the received kernel mode data packet isprovided to or otherwise identified to kernel mode debugging process206. In certain implementations, the kernel mode data packet is providedto or identified to kernel mode debugging process 206 withoutsignificant delay in order to support time-critical processes within thekernel mode debugging operation.

If bridge logic 204 determines that one or more received data packetsare user mode data packets, for example, associated with application 160a, then bridge logic 204 stores or otherwise operatively associates thereceived data packet(s) within one or more buffers within memory 134.Bridge logic 204 notifies or otherwise identifies to virtual miniportlogic 212 that incoming user mode data packets are queued and ready forretrieval. Subsequently, “virtual” miniport logic 212 operating in theuser mode retrieves the stored user mode data packet(s) and provides orotherwise identifies the retrieved data packet(s) to application 160 athrough one or more conventional communication supportingnetwork/transport protocol functions (as applicable), such as, forexample, a TCP/IP function 210 and a Windows Sockets (WinSock) function208.

The above exemplary incoming data packet handling processes areessentially reversed to handle outgoing data packets, based on the typeof outgoing data packet. For example, outgoing kernel mode data packetsgenerated by kernel mode debugging process 206 are provided to orotherwise identified to bridge logic 204. Bridge logic 204 then providesor otherwise identifies the outgoing kernel mode data packets tocommunication port 202, which then proceeds to send the outgoing kernelmode data packet over the network connection. Note, here, communicationport 202 is configured to operate in kernel mode.

When application 160 a generates outgoing user mode data, for example,then the outgoing user mode data is provided or otherwise identifiedthrough, e.g., WinSock function 208 and TCP/IP function 210, to miniportlogic 212 in the form of one or more outgoing user mode data packets.Miniport logic 212 stores or otherwise operatively associates eachoutgoing user mode data packet in one or more buffers within memory 134.Miniport logic 212 notifies or otherwise identifies to OS kernel 158,for example, through a logical event setting or the like, that outgoinguser traffic is queued and waiting to be sent through communication port202. Subsequently, during kernel mode, bridge logic 204 provides orotherwise identifies the queued outgoing user mode data packets tocommunication port 202, which then sends them over the networkconnection.

Those skilled in the art will recognize that a plurality of applications160 may be operatively supported in a similar manner, such that the usermode traffic includes user mode data packets associated with variousapplications.

With the above arrangements in mind, FIG. 4 is a flow diagram thatdepicts a shared communication port data packet transmission process300. In step 302, a user mode data packet (e.g., from an application) isprovided to miniport logic 212. In certain implementations of step 302,for example, a network driver interface specification (NDIS) packet ispassed into miniport logic 212. In step 304, miniport logic 212 obtainsthe necessary buffer space in memory 134. Here, for example, miniportlogic 212 may be configured to use an I/O control (IOCTRL) command, suchas, IOCTRL_VBRIDGE_GET_TX_PACKET, to obtain a kernel buffer from the OSkernel 158. In step 306, miniport logic 212 copies the outgoing usermode data packet to the buffer obtained in step 304. For example, incertain implementations, as part of step 306 miniport logic 212 wouldcopy the WinSock application's data into the applicable kernel buffer.

Next, in step 308, miniport logic 212 identifies the applicablebuffer(s) to bridge logic 204. In step 310, bridge logic 204 queues thebuffered outgoing user mode data packet for transmission. By way ofexample, in certain implementations, miniport logic 212 provides anIOCRTL_VBRIDGE_GET_TX_PACKET_COMPLETE command to OS kernel 158, whichcauses bridge logic 204 to queue the buffered data packet. At thispoint, miniport logic 212 can then return any associated NDIS packets.

In step 312, the OS kernel 158 is notified that an outgoing user modedata packet has been queued for transmission. In certainimplementations, for example, step 312 may include having miniport logic212 trigger an event that OS kernel 158 recognizes or responds to. Next,in step 314, bridge logic 204 provides the outgoing data packet tocommunication port 202. In step 316, the outgoing data packet istransmitted by communication port 202 over the network connection. Forexample, the triggering event may cause a switch to kernel mode, whereinqueued user mode data packets are then provided to communication port202 and transmitted.

When kernel mode debugging process 206 decides to send a kernel modedata packet, then, as in step 318, the outgoing kernel mode data packetis provided to bridge logic 204. Next, in step 314, bridge logic 204provides the outgoing data packet to communication port 202, which, instep 316, transmits the outgoing data packet over the networkconnection.

In certain preferred implementations, kernel mode data packets have ahigher priority than user mode data packets. Thus, in suchimplementations kernel mode data packets will be transmitted before anyqueued user mode data packets are transmitted. Those skilled in the artwill recognize that a producer/consumer queuing arrangement or likecontrollable buffering mechanism may be used to provide the requisitemanagement of the various data packets.

Furthermore, to support time critical debugging processes thetransmission of kernel mode data packets is preferably not significantlydelayed by bridge logic 204 and/or communication port 202.

Attention is now drawn to the flow diagram in FIG. 5, which depicts ashared communication port data packet reception process 400. In step402, a data packet is received and provided by communication port 202 tobridge logic 204. In certain exemplary implementations, the reception ofan incoming data packet causes OS kernel 158 to be interrupted orotherwise notified, such that the incoming data packet is extracted andprovided to bridge logic 204.

Bridge logic 204 is configured to identify if the received data packetis a user mode data packet or a kernel mode data packet. Thus, in step404, if the received data packet is a kernel mode data packet, thenbridge logic 204 provides the received data packet to kernel modedebugging process 206. In certain implementations, the received kernelmode data packet is preferably provided to kernel mode debugging process206 without significant delay since it may be time-critical or otherwiseimportant to an on-going debugging operation. After step 404, process400 returns to step 402.

If bridge logic 204 determines that the received data packet is,instead, a user mode data packet, then in step 406 bridge logic 204queues or otherwise stores the user mode data packet in one or morebuffers, for example, within memory 134. As represented by step 408, ifadditional data packets have been received, then process 400 returns tostep 402 to repeat steps 402 and either 404 or 406 depending upon thetype of data packet received.

Let us assume, for example, that only two data packets were received andthat each data packet was determined to be a user mode data packet.Then, in this example, both user mode data packets would be queued inaccordance with step 406. At this point, with no other data packetsreceived, bridge logic 204 would identify to miniport logic 212 thebuffer(s) used to queue the user mode data packets, as in step 410. Incertain implementations, for example, bridge logic 204 triggers an eventthat identifies that at least one user mode data packet has been queued.

Next, in step 412, miniport logic 212 retrieves the user mode datapacket(s) from the buffer(s). For example, in certain exemplaryimplementations, miniport logic 212 uses IOCTL_VBRIDGE_GET_RX_PACKET toretrieve the data packet(s).

In step 414, miniport logic 212 provides the user mode data packet(s) toone or more communication supporting network/transport protocolfunctions, such as, for example, TCP/IP function 210 and WinSockfunction 208. In step 416, miniport logic 212 releases the buffer(s).Thus, for example, in certain implementations as part of step 416miniport logic 212 completes an indication to NDIS with regard to theuser mode data packet(s) and calls IOCTL_VBRIDGE_GET_RX_PACKET_COMPLETEto return the buffer(s) back to bridge logic 204.

In certain implementations, for example, bridge logic 204 is provided inthe form of a library (Vbridge.lib) that an OEM links to the hardwareadaptation layer (HAL) module. Miniport logic 212 is provided in theform of a dynamic linked library (DLL) (Vmini.dll), which performs as apass through miniport driver. Vmini.dll runs in user mode (preemptable)and Vbridge.lib functions are called in kernel mode (not preemptable).The two modules can communicate via a KernelIOControl( ) code exportedby OS kernel 158, for example, named system interrupt (SYSINTR_VMINI).Here, memory 134 can be reserved by Vbridge.lib. In this exemplaryimplementation, Vmini.dll is configured to follow standard NDIS miniportimplementation techniques.

With the above example in mind, the following is an exemplary listing ofvarious IOCTRL codes and associated functional descriptions thatVmini.dll uses to communicate to the IOCTRL handling provided within OSkernel 158:

-   -   1. IOCTRL_VBRIDGE_GET_TX_PACKET—this function is used by        Vmini.dll to obtain a kernel buffer to be filled with outgoing        user mode data.    -   2. IOCTRL_VBRIDGE_GET_TX_PACKET_COMPLETE—when the buffer is        properly filled, Vmini.dll uses this function to trigger the        kernel's code to start sending out user mode data packets.    -   3. IOCTRL_VBRIDGE_GET_RX_PACKET—when Vmini.dll is notified        (e.g., via a named event) that a user mode packet is available,        Vmini.dll uses this function to obtain access to the kernel        buffer.    -   4. IOCTRL_VBRIDGE_GET_RX_PACKET_COMPLETE—this function is used        by Vmini.dll to return the buffer obtained in        IOCTRL_VBRIDGE_GET_RX_PACKET; when returned, kernel 158 can then        use the buffer for future incoming data packets.    -   5. IOCTRL_VBRIDGE_GET_ETHERNET_MAC—since Vmini.dll and kernel        158 share the same physical Ethernet port, this function allows        Vmini.dll to obtain the medium access controller (MAC) address        of the Ethernet adapter.    -   6. IOCTRL_VBRIDGE_CURRENT_PACKET_FILTER—this function allows        Vmini.dll to selectively specify the filter that is to be used        by the underlying Ethernet hardware while receiving incoming        data packets.    -   7. IOCTRL_VBRIDGE_(—)802_(—)3_MULTICAST_LIST—this function        allows Vmini.dll to pass in multicast address lists that WinSock        application 160 a, for example, wants to listen to.    -   8. IOCTRL_VBRIDGE_SHARED_ETHERNET—this function allows Vmini.dll        to determine whether the particular kernel it is running can        support the shared communication port methods and apparatuses,        for example, as provided therein.

Based on the foregoing descriptions, it can be seen that devices, suchas device A 102 (FIG. 1) can be configured through the addition of“virtual” miniport logic 212 and “virtual” bridge logic 204 to supportboth kernel mode data packets and user mode data packets through acommon shared communications port 202. This allows, for example, kernelmode debugging operations to be conducted while one or more applicationsare running. Such debugging may take place during manufacture, forexample, by the OEM. Moreover, such debugging may also take placeremotely, for example, over a LAN, WAN, the Internet, an intranet, orthe like.

Although some preferred embodiments of the various methods andapparatuses of the present invention have been illustrated in theaccompanying Drawings and described in the foregoing DetailedDescription, it will be understood that the invention is not limited tothe exemplary embodiments disclosed, but is capable of numerousrearrangements, modifications and substitutions without departing fromthe spirit of the invention as set forth and defined by the followingclaims.

1. A method comprising: providing at least one processing unit toselectively run user mode logic and kernel mode logic; receiving atleast one data packet through a shared communication port; and whilesaid processing unit is running said kernel mode logic, selectivelyhandling said data packet for use with either said user mode logic orsaid kernel mode logic, wherein said processing unit is included withina device having only one physical network communication port, whichoperates as said shared communication port.
 2. A computer readable mediahaving computer instructions for performing acts comprising: selectivelyrunning at least one processing unit using either user mode logic orkernel mode logic; receiving at least one data packet through a sharedcommunication port; and while running said kernel mode logic,selectively handling said data packet for use with either said user modelogic or said kernel mode logic, wherein said processing unit isincluded within a device having only one physical network communicationport, which operates as said shared communication port.
 3. An apparatuscomprising: a single physical network communication port that operatesas a shared communication port; and at least one processing unit that isconfigured to: seleciively run using either user mode logic or kernelmode logic; receiving at least one data packet through the sharedcommunication port; and while running said kernel mode logic,selectively handling said data packet for use with either said user modelogic or said kernel mode logic.